Glad to have you joining us, Milo. You’ll find lots of help here on G2G. Also there are excellent resources on starting out. Here’s a good one...
https://www.wikitree.com/wiki/Help:How_to_Use_WikiTree
Many links there. My suggestions for starting out:
1. Go slow. Taking your time will assist you in not having to go back and correct mistakes.
2. Ask 1000 questions! Any question you ask will be answered to the best of the community’s ability. I’ve asked some obscure things on G2G, and have always received an answer, and even if info couldn’t be found I got some good leads. And your questions will help others that may have the same puzzled look! 
Once again, welcome! I hope your experience on WikiTree is as enjoyable and profitable as mine has been.